I have a 92 sc4000 and my right Lo Beam went out the other day and when I replaced it, it immediately burnt out. I am assuming it is a short as the fuses seem to be ok.
What can I do to know for sure that this is the problem? Or, should I just bring it to a shop and let them deal with it...thanks.

 

how did you replace it?

 

I just took out the old bulb and put in a new one. then turned the lights on.

 

Did you touch the actual bulb's glass with your finger tips in any way? These bulbs can self distruct real quickly if you get any oil from your finger tips on them.

 

I don't think so, but it is a possibility...I actually went through 2 bulbs...
I put a new one in and it blew, then took the one installed on the other side and it blew too....
I didn't notice any condensation in there so I didn't think that was the problem.

 

Check the voltage on the side that is not blowing bulbs and then check the voltage on the side that is blowing bulbs. However, I doubt the problem is a high voltage situation.

 

I recently took out the stock airbox and put in a K&N cone filter...but that shouldn't have had any effect. I inspected the wiring and didn't notice anything.

 

make sure to ground yourself before touching any electricity. EVEN light bulbs. You never can tell.

 

messysc, when you say they "burnt out immediately", how fast are we talking here? 10 secs? Instantaneous? Are they "burnt out" as in the filament in the bulb is melted into two pieces? What type of bulb are you using in the LB? They should be 55w 9006.

When I'm dealing with live wires, I never touch anything but the live wire itself. I've never tried this myself because I'm not that curious, but if you were to touch the frame of the car while making contact with the live, in theory (based on my basic knowledge on dc) you'd create a complete circuit and electricity would surge through you! Especially since the lighting circuits are switched grounds when off and there is no other grounding for that line other than yourself. If the current in that wire is high enough, you'll feel it. Regardless, he shouldn't encounter any wires when replacing the LB, just screw the bulb into the socket, and plug a harness in.

 

Anthracite,
It burnt out in about 2 seconds. The filament looks ok but when I switched out the bulb that quit with the good one on the left side and it still didn't work. After I lost 2 bulbs I kinda quit doing this...
they are just stock 9006 bulbs. ????

 

I would take the car to the dealer. Its not worth your safety to only have one headlamp. Maybe you should switch to HIDs.... it would fix your problem and you would have better lighting.